The invention relates to a system and a method for controlling an ultrasound generator of a machine tool for generating ultrasound for machining a workpiece. According to the invention, a determined phase shift of the ultrasound is analyzed as a function of frequency and, based on the analysis, a regulation algorithm for controlling the frequency of the ultrasound generated by the ultrasound generator is determined.

An amplifier circuit to be used in a sonar is described. The amplifier circuit includes a transducer and a matching circuit. The transducer has an impedance characteristic having a resonance frequency and an anti-resonance frequency higher than the resonance frequency. The matching circuit is connected to the transducer. The impedance characteristic of the transducer connected to the matching circuit has a first resonance frequency and a second resonance frequency higher than the first resonance frequency.

Road vehicle comprising at least one electric motor; an acoustic system, which comprises at least one reproduction device, which generates a sound that can be associated with the electric motor; wherein the electric motor is mechanically connected to the reproduction device so as to be able to excite a resonant frequency thereof; and a control unit configured to control the electric motor so as to inject at least one sonority current or voltage, as an input, to the electric motor itself; wherein said at least one sonority current or voltage excites a frequency resulting in a vibration of said at least one reproduction device, which emits, due to the vibration, in the form of acoustic waves, a sound as a function of the injected sonority current or voltage.

Various methods and systems are provided for a multi-frequency transducer array. In one example, the transducer array is fabricated by forming an interdigitated structure from a first comb structure with a first sub-element and a second comb structure with a second sub-element. The interdigitated structure is coupled to a base package, a matching layer, and a backing layer to form a plurality of multi-frequency transducers.

An ultrasonic/megasonic cleaning device includes a cleaning unit including an upper casing and a lower casing connected to form a hollow chamber, an ultrasonic/megasonic generator provided in the hollow chamber, and a bottom quartz component provided with a quartz rod array composed of a plurality of vertically arranged quartz rod-like structures; a spray arm connected to the upper casing; and an ultrasonic/megasonic frequency control unit connected between the at least one signal source and the ultrasonic/megasonic generator, for constantly varying a frequency of the electrical signal output from the at least one signal source and introducing the electrical signal into the ultrasonic/megasonic generator, so as to dynamically vary an oscillation frequency of the ultrasonic/megasonic wave generated by the ultrasonic/megasonic generator; wherein the ultrasonic/megasonic frequency control unit includes a frequency-switching timing control unit configured to trigger am ultrasonic/megasonic frequency switching control unit to switch the oscillation frequency of the ultrasonic/megasonic wave from a first frequency to a second frequency when the ultrasonic/megasonic wave has been generated at the first frequency for a time period, the time period being randomly selected within a time range.

A wearable element is disclosed. In an embodiment a wearable element includes at least one piezoelectric element configured to vibrate so that a haptic impression of an acoustic signal is generated, wherein the wearable element is wearable on a body.

Disclosed herein a method of producing an ultrasound that includes defining a set of criteria for an ultrasound emitter comprising a plate. The set of criteria includes a power output criterion, a frequency criterion and number of nodes for a resonance mode of the plate, a focus criterion, and a durability criterion. The method includes determining an outline and a thickness range for the plate, based on the set of criteria. The method includes using topology optimization to determine internodal zone dimensions for the plate, based on the set of criteria, the outline, and the thickness range. The method includes manufacturing the plate according to the internodal zone dimensions.

A method for removing foreign substances from a camera system is provided. The camera system includes a camera device with a transparent cover having a piezoelectric component. First, a type of the foreign substances is identified based on temperature, an image captured by the camera system, and a voltage change of the piezoelectric component. A sequence of frequencies is applied to the piezoelectric component and a resonant frequency is acquired. Thereafter, the foreign substances are removed from the camera system. A vibration frequency and a vibration time period for the piezoelectric component are determined according to the identified type of the foreign substances. The vibration frequency is based on the resonant frequency. The piezoelectric component is driven with the vibration frequency and the vibration time period, such that at least a portion of the foreign substances are removed from the transparent cover through vibration of the piezoelectric component.

An ultrasonic device includes a driving circuit to provide drive power, a first transducer array to generate ultrasonic waves, the first transducer array being connected to receive power from the driving circuit, and a second transducer array to detect reflected or elicited ultrasonic waves incident on the device from a target and generate a signal based on those waves, the second transducer array being acoustically transmissive and disposed over the first transducer array such that the generated ultrasonic waves pass through the second transducer array. The second array is tuned to operate on top of the first. The functions of the two arrays may be reversed and the array tuned to operate with the first array receiving and the second array transmitting.

An ultrasonic device, comprising an ultrasonic transducer (400) comprising: a membrane (405) suspended above a cavity (403) arranged on the upper surface side of a substrate (401); a piezoelectric layer (407) attached to a surface of the membrane (405); a first electrode (E1) arranged on the lower surface side of the cavity (403); and a second electrode (E3) arranged on the upper surface side of the cavity (403), in contact with the piezoelectric layer (407), the device further comprising a control circuit (CTRL) connected to the first (E1) and second (E3) electrodes and capable of applying a first control voltage (VDC) on the first electrode (E1), and a second control voltage (VAC) different from the first voltage on the second electrode (E3).